0 votes
29 views
ago in ElectroChemistry by (270 points)
Consider a zinc electrode in a concentration cell that is connected to a copper electrode through a salt bridge. During the electrolysis of an aqueous solution of ZnSO4, a current of 2.5 A is passed through the cell for 20 minutes. Calculate the mass of zinc deposited on the electrode during this time assuming 100% efficiency. (Molar mass of zinc = 65.38 g/mol)

1 Answer

0 votes
ago by (510 points)
To calculate the mass of zinc deposited on the electrode, we can use Faraday's law of electrolysis. Faraday's law states that the amount of substance deposited or dissolved at an electrode is directly proportional to the amount of charge passed through the cell.First, we need to find the total charge passed through the cell. We know that current  I  is equal to the charge  Q  divided by time  t . Rearranging this equation, we get:Q = I  tGiven the current  I  is 2.5 A and the time  t  is 20 minutes  which we need to convert to seconds , we can calculate the total charge:Q = 2.5 A   20  60  s = 2.5 A  1200 s = 3000 C  Coulombs Now, we need to find the number of moles of electrons passed through the cell. We can use Faraday's constant  F , which is approximately 96485 C/mol:n = Q / F = 3000 C / 96485 C/mol  0.0311 mol of electronsThe balanced half-reaction for the deposition of zinc is:Zn + 2e  ZnFrom the stoichiometry of the reaction, we can see that 2 moles of electrons are required to deposit 1 mole of zinc. Therefore, we can find the number of moles of zinc deposited:moles of Zn = 0.0311 mol of electrons / 2 = 0.01555 mol of ZnFinally, we can calculate the mass of zinc deposited using the molar mass of zinc  65.38 g/mol :mass of Zn = 0.01555 mol of Zn  65.38 g/mol  1.016 gSo, the mass of zinc deposited on the electrode during this time is approximately 1.016 g, assuming 100% efficiency.

Related questions

Welcome to Sarvan Science Q&A, where you can ask questions and receive answers from other members of the community.
...